Turbosupercharger system



July 31', 194s. s. A. M555 2,380,711

TURBOSUPERCHARGER SYSTEM Filed May 4, 1942 Inventor: Sanford A .Moss,

His Attorney.

Patented July 31, 1945 UNITED STATES PATENT ounce 'ruaaosurnncnsacan srsrnm Sanford A. Moss, Lynn, Mala, allignorto General Electric Company, a corporation of New York Application May 4, 1042, Serial No. 441,115

' 13 Claims.

In the drawing, the figure is a diagrammatic view of a turbosupercharger installation embodying my invention.

Referring to the drawing, l indicates a part of an aircraft in which is enclosed an internal combustion engine which drives a propeller 2. The carburetor for the engine is indicated at 3 from which the explosive mixture is conveyed to the intake manifold of the engine through a conduit I.

, Connected with the exhaust manifold of the engine is a conduit 5 for conveying exhaust gases to the turbosuperchargers.

I and 1 indicate two turbosuperchargers connected in parallel. The nozzle box for supercharger 6 is indicated at I, the turbine wheel is indicated at i, and the centrifugal compressor is indicated at II. The air intake for the compressor IB is indicated at ii and the discharge conduit is indicated at l2. The nozzle box for turbosupercharger I is indicated at IS, the turbine wheel is indicated at I4, and the centrifugal compressor is indicated at II. The inlet for compressor II is indicated at I. and the discharge conduit is indicated at l'l. Discharge conduits l2 and H are connected in parallel to the carburetor I by a conduit It. Nozzle boxes 0 and I! are connected to exhaust gas conduit I by conduits It and 2|, re-

- spectivehn' Connected with conduit 5 is a waste conduit 2| in which is located a suitable waste gate valve 22 which regulates the flow of exhaust ases to the nozzle boxes. when waste gate valve 22 is wide open, the exhaust'gases from the engine discharge directly to atmosphere, little if any gases passing through the respective nozzle boxes. This represents the condition of no load on the superchargers. As waste gate valve 22 is gradually closed, more and more of the gases are directed to the nozzle boxes from whence they are discharged through the rings of nozzles to the turbine wheels. Maximum load condition obtains when the waste gate valve is completely closed, all

wheels. Waste gate valve 22 may be controlled in any suitable manner, either manually or automatically. In the present instance, it is shown asbeing providedwithacrankarmfltowhich'ls connected a rod 24 which may go to the means for positioning the waste gate valve.

It is known that when two centrifugal compressors are operated in parallel, if the load on them as imposed by external conditions is such as to require both of them. they operate with complete stability. If, however, the load is so light as to bring the two compressors near their pulsation points, thenone tends to take all the load and to drive the other backwards. The point at which pulsation starts in a compressor is known as the breakdown point and depends upona number of factors, including the volume and the pressure.

According to my invention, 1 select t o coinpressors having somewhat diilerent characteristic curves, one having a pulsation point or breakdown point somewhat ahead of the other and I then provide the one compressor which has the earlier breakdown point with means for shutting down the flow of air through'it and means. for shutting off the. flow of operating gas to it when the load on the compressors reaches sucha low value that the breakdown point of the one compressor is approached.

In the present instance, the compressor I. has a breakdown point or pulsation point ahead of the compressor i5 and according to my invention, I provide in discharge conduit l2 a valve 25 for shutting oifthe flow of air throllah' conduit 12 and in conduit II a valve 26 for shutting oi! the flow of gases to home box I. Valves 2! and 26 are connected together by a link 21 which atone end ,isconnectedtoanarmtlfixedonthespindleof th gasesbeingthendlrectedtotheee valve 25 andatthe other-endisconnectedto'one end of a lever 2| mounted on a fixed pivot 32 and having its other end pivotally connected to an arm ii on the spindle of valve 26. Thus. the two valves 2! and 26 are constrained to move together, being opened and closed simultaneously. Preferably, I provide in theconduit l2 an aperture 22 which is open to atmosphereand which is normally closed by a valve 32 connected by a link 3 to an arm 3| on the valve spindle of valve 2|. the arrangement being such that when valve 28 is closed, valve 32 is opened and vice versa.

During normal operation, valves 25 and 2t stand in wide open position and valve it closes aperture 32. The arrangement is such that valve 2-! is biased toward closed position and is held open by the flow of air through conduit 12. with normal loads 1! .r valves 25 and 26 will both be open and exhaust gases from conduit I will be supplied to both male boxes I and II, the two turbosupercharg'ers operatin in parallel. Now, if the load decreases to a point approaching the pulsation or breakdown point of centrifugal compressor it, the flow of air through conduit I! will decrease to a point such that valve 25 will drop to closedposition, the movement or valve II simultaneously effecting the closing oi valve II and the opening of valve 33. This shuts down supercharger t whereupon the entir load is assumed by supercharger I. Preferably, the arrangement is such that valve II, when moved to closed position, does not completely close conduit II but permits suflicient gas to flow past it to operate I supercharger i at an idling speed. The uncovering of aperture 32 permits suiilcient air now through compressor II to prevent its overheating. Preferably, the idling speed at which supercharger l is operated is suillciently high. to enable it to again take its part of the load promptly when occasion demands. Now, so long as the load imposed externally is one so small that only one supercharger is required to carry it, the operation continues as just described, the supercharger 'l carrying the entire load. It now the load on supercharger 5 increases, the pressure produced by it gradually decreases and when the load increases to a value such that the pressure delivered by the compressor it is less than the light load or idling load pressure maintained by supercharger is, valve 26 will be opened by the air pressure in conduit l2 whereupon the two superchargers will again begin we operate in parallel.

Thus, by my invention, I am enabled tooperate two turbosuperchargers in parallel without pulsation occurring until the load decreases to a value at which it reaches th breakdown pressure of the second compressor, in the present instance the compressor it.

In accordance with the provisions of the pat erit statutes, I have described the principle of operation of my invention, together with thesppal'atus which I now consider to represent the best embodiment thereof, but I desire to have it understood that the appar tus shown is only illustratlve and that the invention may be carried out by other means.

What I claim as new and desire to secure by Letters Patent of the United States, is,

1. In combination, a plurality of superchargerseachcomprisingagastumineandacentriiugal compressor, means for supplyin gases to the turbines in parallel from a source of supply, means connecting the discharge sides of the compressors in parallel with each other to a point of consumption, and means operated automatically when the load on the compressors reaches a p determined low value for idling one or the superchargers. I

2. In combination, a plurality of superchargers each comprising a gas turbine and a centrifugaLeompr-essor, means for supplying gases to the turbines in arallel from a source oi supply, means connecting the discharge sides or the compressorsinpelwitheachothertoapointof consumption, an meansoperated automatically when the load on the compressors reaches a predetermined low value for closing the air discharge conduit at one supercharger and simultaneously shutting oi! the sup ly of gases thereto.

3- In combination, a plurality of superchargers each comprising a gas turbine and a centrifugalcompressonmeansiorsupplyinggaseatothe turbines in parallel from a source of supply,

acne-:77

means connecting the discharge sides of the comprcssors in parallel with each other to a point of consumption, one of said compressors having an earlier pulsation point than the other, and means 5 for closing the air discharge conduit and for shutting ofl the supply of gases to the supercharger having the compressor with. the earlier pulsation point when the load on the compressors reaches a predetermined low value.

4. The combination with an internal combustion engine, of a plurality of superchargers each comprising a centrifugal compressor having its discharge conduit connected to. the engine intake and a gas turbine having its inlet connected to the engine exhaust, one of said compressors having an earlier pulsation point than the other, and means for automaticall shutting down the supercharger having the compressor with the earlier pulsation point when the load on the com prcssors reaches a predetermined low value.

5. The -combination with an internal combustion engine of a plurality of superchargers each comprising a centrifugal compressor having its discharge conduit connected to the eng e intake and a gas turbine having its inlet connected to the engine exhaust, one of said compressors having an earlier pulsation point than th other, a valve in the discharge conduit of said one compressor, a valve in the inlet of the turbine which so drivessaid one compressor, and means for automatically closing said valves when the load on the compressors reaches a predetermined low value.

6. In combination, a plurality of superchargers each comprising a gas turbine and a centrifugal 35 compressor, means for supplying gases to the turbines in parallel from a source of supply, means connecting the discharge sides'oi the compressors in parallel wltheach other to a. point of consumption, and means operated auto- 40 matically when the low on the compressors reaches a. predetermined low value for shutting on the how oi air through the discharge conduit of one supercharger and connecting such conduit to a region of lower pressure and simultaneously diminishing the supply gases thereto to operate it at idling speed.

.7. In combination, a plurality of superchargers each comprising a gas turbine and a centrifugal compressor. means for supplying gases to the turbines in parallel from a source of supply,

means connecting the discharge sides of the compressors in parallel with each other to a point of consumption, one of said compressors having an earlier pulsation point than the other, and means for shutting oi! the now of air through the. discharge conduit of the supercharger having the compressor with the earlier pulsation point and connecting such conduit to a region of lowerpressure when the load on the compressor reaches a predetermined low value, and simultaneously diminishing the supply of gases thereto to operate it at idling speed.

a. The combination with an internal combustion engine of a plurality of superchargers each comprising a centrifugal compressor having its discharge conduit connected to the engine intake and a gas turbine havinglts inlet connected to the engine exhaust, one of said compressors having an earlier pulsation point than the other, a valve in the discharge conduit of said one compressor, a valve in the inlet of the turbine which drives said one compressor, means for automatically closing said valves when the load on the compressors reaches a predetermined low (I value, and means eilectivc when said valves are closed for operating said one compressor at idling speed and connecting-its discharge in advance of said first named valve to-a region of lower pressure.

9. The combination with an internal combustion engine of a plurality of superchargers each comprising a centrifugal compressor having its discharge conduit connected to the engine intake and a gas turbine having its inlet connected to the engine exhaust, one of said compressors having an earlier pulsation point than the other, valve means in the discharge conduit of said one compressor for shutting off the flow therethrough and connecting such conduit to a region of lower pressure, valve means in the inlet of the turbine which drives said one compressor, and means for effecting simultaneous operation of said valve means when the load on the compressor reachessupply, means connecting the discharge sides of the compressors in parallel with each other to a point of consumption, and means operated automatically when the load on the compressors reaches a predetermined low value for idling one of the units.

11. In combination, a plurality of units each comprising a prime mover and a centrifugal compressor, means for supplying actuating ;fluid to the prime movers in parallel from a source of supply, means connecting the discharge sides of the compressors in parallel with each other to a point of consumption, and means operated auto- 'matically when the load on the compressors reaches a predetermined low value for closing the air discharge conduit of one compressor and simultaneously shutting oi the supply of actuating fluid thereto.

12. In combination, a plurality of units each comprising a prime mover and a centrifugal compressor, means for-supplying actuating fluid to the prime movers in parallel from a source of supply, means-connecting the discharge sides of 'the compressors in parallel with each other to a comprising a centrifugal compressor and a driving means therefonmeans connecting the discharge sides of the compressors in parallel with each other to a point of consumption, and means operated automatically when theload on the compressors reaches a predetermined low value for shutting off the flow of air through the discharge conduit of one compressor and simultaneously shutting down the driving means therefor.

SANFORD A. MOSS. 

